Electric actuator with bidirectional compliance

Abstract

An adjustable electric actuator system includes an actuator output, a compliance element coupled to the actuator output, and an end fitting element encapsulating at least a portion of the compliance element, wherein the compliance element is guided a first distance in a first axial direction by the actuator output, the first distance being limited by a first limitation element.

1 . An adjustable electric actuator system, comprising:
 an actuator output;   a compliance element coupled to said actuator output; and   an end fitting element encapsulating at least a portion of said compliance element, wherein said compliance element is guided a first distance in a first axial direction by said actuator output, said first distance being limited by a first limitation element.   
     
     
         2 . The adjustable electric actuator system of  claim 1 , wherein said compliance element is guided a second distance in a second axial direction by said actuator output, said second distance being limited by a second limitation element. 
     
     
         3 . The adjustable electric actuator system of  claim 1 , wherein said first limitation element is at least one of a spring element, a pad, or a metal element. 
     
     
         4 . The adjustable electric actuator system of  claim 1 , wherein said actuator output is a shaft. 
     
     
         5 . The adjustable electric actuator system of  claim 1 , wherein said compliance element is guided said first distance from a mid-position, and is returned to said mid-position after said compliance element is guided said first distance from said mid-position or after said compliance element is guided a second distance in a second axial direction by said actuator output, said second distance being limited by a second limitation element. 
     
     
         6 . The adjustable electric actuator system of  claim 3 , wherein said metal element protrudes from a center position of said end fitting element. 
     
     
         7 . The adjustable electric actuator system of  claim 2 , wherein said first distance and said second distance combine for total actuator overtravel. 
     
     
         8 . The adjustable electric actuator system of  claim 3 , wherein when said first limitation element is said spring element, said compliance element has an associated spring load at maximum spring travel in said first axial direction and a second axial direction less than an overall actuator static limit load. 
     
     
         9 . The adjustable electric actuator system of  claim 2 , wherein said first distance in said first axial direction and said second distance in said second axial direction combine to form bi-directional compliance in an axial direction parallel to an actuator force in said axial direction and in series with said actuator output coupled to said end fitting element. 
     
     
         10 . An adjustable electric actuator system, comprising:
 an actuator output;   a compliance element coupled to said actuator output; and   an end fitting element encapsulating at least a portion of said compliance element, wherein said compliance element is guided a first distance in a first axial direction by said actuator output, said first distance being limited by a first limitation-retraction element.   
     
     
         11 . The adjustable electric actuator system of  claim 10 , wherein said compliance element is retracted a second distance in a second axial direction by said first limitation-retraction element. 
     
     
         12 . The adjustable electric actuator system of  claim 11 , wherein said second distance is limited by a second limitation-retraction element. 
     
     
         13 . The adjustable electric actuator system of  claim 12 , wherein said first limitation-retraction element is a first plurality of springs. 
     
     
         14 . The adjustable electric actuator system of  claim 13 , wherein said second limitation-retraction element is a second plurality of springs. 
     
     
         15 . The adjustable electric actuator system of  claim 14 , wherein said second plurality of springs surround a portion of a rod of said compliance element. 
     
     
         16 . The adjustable electric actuator system of  claim 14 , wherein said first plurality of springs are Belleville washers and said second plurality of springs are Belleville washers. 
     
     
         17 . A method of adjusting an electric actuator, comprising:
 guiding a compliance element encapsulated by an end fitting element a first distance in a first axial direction using an actuator output; and   limiting said first distance using a first limitation-retraction element positioned axially between said compliance element and said end fitting element.   
     
     
         18 . The method of  claim 17 , further comprising guiding said compliance element a second distance in a second axial direction using said actuator output. 
     
     
         19 . The method of  claim 18 , further comprising limiting said second distance using a second limitation-retraction element. 
     
     
         20 . The method of  claim 18 , further comprising returning said compliance element to a mid-position after said compliance element is guided said first distance or after said compliance element is guided said second distance.